One vertex per element, one color per generator, with an edge from x to x·s.
(1,2)(3,7)(4,8)(5,6)(9,10,14,12)(11,17,19,15)(13,16,21,20)(18,23,24,22)(25,26)(27,29)(28,36)(30,31)(32,34)(33,37)(35,40)(38,39)(2,6)(3,8)(10,12)(15,17)(16,20)(22,23)(26,31)(27,34)(28,37)(39,40) involution — undirected(1,3)(2,4)(5,8)(6,7)(13,21)(16,20)(18,24)(22,23)(26,31)(29,32)(33,36)(39,40) involution — undirected(1,3)(2,4)(5,8)(6,7)(9,11,14,19)(10,15,12,17)(13,18,21,24)(16,22,20,23)(25,27)(26,32)(28,38)(29,31)(30,34)(33,39)(35,37)(36,40)(1,4)(2,3)(5,7)(6,8)(9,12,14,10)(11,15,19,17)(13,20,21,16)(18,22,24,23)(25,28)(26,33)(27,35)(29,39)(30,37)(31,36)(32,40)(34,38)(9,13,14,21)(10,16,12,20)(11,18,19,24)(15,22,17,23)(25,29,30,32)(26,27,31,34)(28,39,37,40)(33,35,36,38)A Cayley diagram is a choice, not a fact about the group. Another drawing of this group — in a book, or on a different generating set — may look nothing like this one.